need some help diagnosing this electrical issue - VIDEO

[iamsuperbleeder]

Got a little glitch going on with my SCX10 (well, I say "little", but it's all but made the truck undriveable...). This all started today after hooking up a Traxxas 7 cell 8.4v battery to the rig for the first time and taking it for a test drive out in the drive way. Maybe that has something to do with it, I dunno, but that's why I threw that in there . It was working fine for the first 5 minutes or so during the test drive (long enough to break a drive shaft, but that's another issue, lol), but after cruising in 2wd for a little while, I noticed it started losing power in reverse. Then it started to act funny when trying to go forward. It's gradually gotten worse up to the point of this video, where as you can see, reverse is almost non-existent right now, and forward is hit and miss (mostly miss).

My assumption is the ESC. The steering works perfectly fine; no glitches there.

Stock Axial AE-2 ESC, AR-2 receiver, 27 turn brushed motor, and steering servo. The only thing that isn't stock is the wiring obviously. I've moved everything into project boxes and waterproofed them. I've checked, double checked, triple checked, and then checked again, every wire and connecter on the thing, and everything is in top shape, so I'm pretty sure it's not a connection issue. And even though I prepped the rig to be waterproof, I have yet to submerge it; the electronics have stayed dry. The rig had been performing great up until today.

First video is just me showing the response from the ESC to the transmitter and receiver. In the second video I start off showing the voltage right from the battery, and as you can see it's fully charged. Then I move to the motor output power and show the power it's getting when I hit the throttle.


http://www.youtube.com/watch?v=QiMqsUBiX6w



thanks!

[buggynutt]

I dont know if the newer axial electronics are any better but the ae-1 stuff gave me all kinds of problems. They didnt seem to work well with anything new added..I would say you should try a new ecs or contact axial and see what they say. They might send you a new esc if its not to old.

[omenwolf]

Ok its your voltage cutoff messing you up. You need to turn it off when running a nimh especially a 7 cell. When you first plug it in you 3 beeps that means the esc thinks you have a 3 cell lipo plugged in but you dont. a 7 cell 8.4v will have enough peak voltage to think its a 3s lipo but but the voltage doesnt hold long enough and you hit your voltage cutoff. The ae-2 esc has auto lipo set from the factory so you will need to get a castle link to chang the cutoff to "no cutoff" or you can get the feild program card or you can program it through the remote. if you have a 6 cell nimh or a 2s or 3s lipo it will work fine.

[AG74683]

Originally Posted by omenwolf

Ok its your voltage cutoff messing you up. You need to turn it off when running a nimh especially a 7 cell. When you first plug it in you 3 beeps that means the esc thinks you have a 3 cell lipo plugged in but you dont. a 7 cell 8.4v will have enough peak voltage to think its a 3s lipo but but the voltage doesnt hold long enough and you hit your voltage cutoff. The ae-2 esc has auto lipo set from the factory so you will need to get a castle link to chang the cutoff to "no cutoff" or you can get the feild program card or you can program it through the remote. if you have a 6 cell nimh or a 2s or 3s lipo it will work fine.

Seconded. NimH's don't discharge the same way as Lipo's. Basically a NimH is losing power the entire time you use it, a Lipo only loses power right at the end, and thats when the voltage cut off kicks in to prevent you from overdischarging your lipo.

Think of it as a curve, the NimH is a gradual downward slope, the Lipo is a straight line and then a total drop off.

[iamsuperbleeder]

ah, I see! thank you!

it didn't even cross my mind that the ESC might think it's plugged into a 3s lipo, considering it's only suppose to be compatible with a 2s I did notice the extra beep, but honestly didn't think much of it

I'll charge my 6-cell this afternoon and plug it in and see if the problem goes away


regardless, I guess I'm upgrading the ESC soon to take advantage of the two 7 cell packs I have

[omenwolf]

If all you have is nimh i would still reprogram it. You can do it through the remote but its a pain. see if anyone you know has a castle link that could help you.

[iamsuperbleeder]

Originally Posted by omenwolf

If all you have is nimh i would still reprogram it. You can do it through the remote but its a pain. see if anyone you know has a castle link that could help you.

I'll look into programming it through the remote. I don't know anybody off the top of my head who's got a cable

[iamsuperbleeder]

found the programming instructions

http://axialracing.com/wordpress/201...d-programming/


trying it this afternoon!

[version_three]

Originally Posted by iamsuperbleeder

I'll look into programming it through the remote. I don't know anybody off the top of my head who's got a cable

I can bring my laptop and castle link out to Sanford on Sunday

[Big Daddy]

It is kind of a pain but it does work. Before I went LiPo I changed mine. Just remember that if you go into that menu you have to set ALL settings to where you want them not just the one you want to change. I went in and just changed the LVC and then accepted the others and I had little/no drag brake.

[AsILayDying]

I will also bring my CC field programmer and you are more then welcome to use it if you would like. Hope it all works out for you.....

[iamsuperbleeder]

well I'll be damned... just programmed through the remote and disabled the cut off. FULL THROTTLE BOTH WAYS AGAIN!

we're back in business!

thanks a ton guys!

[Charlie-III]

Cool deal, glad the previous suggestions worked out (sorta what I figured).

Also for replying back so this is closed out for the next guy that does a search!

[Trubble]

Also caught your Power Brake video, nice.

[iamsuperbleeder]

Originally Posted by Trubble

Also caught your Power Brake video, nice.

like that huh?

[Trubble]

Yup. Impressed, doesn't seem to be a mark left on the floor. The concrete floor in our basement hasn't been as lucky.